TY - JOUR
T1 - The X-ray structure of photosystem II reveals a novel electron transport pathway between P680, cytochrome b559 and the energy-quenching cation, ChlZ+
AU - Vasil'ev, Sergej
AU - Brudvig, Gary W.
AU - Bruce, Doug
N1 - Funding Information:
We thank J.-R. Shen and N. Kamiya for early access to their X-ray structure for PSII from Thermosynechococcus vulcanus . D.B. is supported by the Natural Sciences and Engineering Research Council of Canada. G.W.B. is supported by the U.S. Department of Energy, Office of Basic Energy Sciences, under Contract DE-F-G02-01ER15281.
PY - 2003/5/22
Y1 - 2003/5/22
N2 - When water oxidation by photosystem II (PSII) is impaired, an oxidized chlorophyll (ChlZ+) is formed that quenches excitation and may prevent photodamage. Both the identification of this Chl+ and the mechanism of its oxidation and reduction are controversial. Using the available X-ray structures of PSII we calculated the efficiency of two proposed quenchers, ChlZ+(D1) and ChlZ+(D2). Of these two, only ChlZ+(D1) can quench to the degree observed experimentally. We also identify a chain of closely spaced pigments in the structure from Thermosynechococcus vulcanus that we propose to form a novel electron transport pathway between ChlZ(D1), β-carotene, P680+ and cytochrome b559.
AB - When water oxidation by photosystem II (PSII) is impaired, an oxidized chlorophyll (ChlZ+) is formed that quenches excitation and may prevent photodamage. Both the identification of this Chl+ and the mechanism of its oxidation and reduction are controversial. Using the available X-ray structures of PSII we calculated the efficiency of two proposed quenchers, ChlZ+(D1) and ChlZ+(D2). Of these two, only ChlZ+(D1) can quench to the degree observed experimentally. We also identify a chain of closely spaced pigments in the structure from Thermosynechococcus vulcanus that we propose to form a novel electron transport pathway between ChlZ(D1), β-carotene, P680+ and cytochrome b559.
KW - Chlorophyll fluorescence
KW - Electron transport
KW - Excitation energy transfer
KW - Non-photochemical quenching
KW - Photosynthesis
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U2 - 10.1016/S0014-5793(03)00442-3
DO - 10.1016/S0014-5793(03)00442-3
M3 - Article
C2 - 12753925
AN - SCOPUS:0038054644
VL - 543
SP - 159
EP - 163
JO - FEBS Letters
JF - FEBS Letters
SN - 0014-5793
IS - 1-3
ER -